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IP subnet calculator

Type an address with its prefix or mask to see the network, its usable range and masks. Split it into smaller subnets, or look up any prefix in the reference tables.

Network40.167.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
40.167.0.0
Broadcast address
40.167.255.255
First usable
40.167.0.1
Last usable
40.167.255.254
Usable hosts
65,534 (65,536 less the network and broadcast addresses)
Subnet mask
255.255.0.0
Wildcard mask
0.0.255.255 (Cisco ACLs, OSPF)
Prefix length
/16
Type
Public public
Old class
A (default /8)
As numbers
Hex 28A70000 · Integer 682033152 to 682098687
Reverse DNS zone
167.40.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00101000.10100111..00000000.0000000040.167.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network00101000.10100111..00000000.0000000040.167.0.0
Broadcast00101000.10100111..11111111.1111111140.167.255.255
Split into smaller subnets/23

40.167.0.0/16 makes 128 subnets of /23.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
140.167.0.0/2340.167.0.1 to 40.167.1.25440.167.1.255510
240.167.2.0/2340.167.2.1 to 40.167.3.25440.167.3.255510
340.167.4.0/2340.167.4.1 to 40.167.5.25440.167.5.255510
440.167.6.0/2340.167.6.1 to 40.167.7.25440.167.7.255510
540.167.8.0/2340.167.8.1 to 40.167.9.25440.167.9.255510
640.167.10.0/2340.167.10.1 to 40.167.11.25440.167.11.255510
740.167.12.0/2340.167.12.1 to 40.167.13.25440.167.13.255510
840.167.14.0/2340.167.14.1 to 40.167.15.25440.167.15.255510
940.167.16.0/2340.167.16.1 to 40.167.17.25440.167.17.255510
1040.167.18.0/2340.167.18.1 to 40.167.19.25440.167.19.255510
1140.167.20.0/2340.167.20.1 to 40.167.21.25440.167.21.255510
1240.167.22.0/2340.167.22.1 to 40.167.23.25440.167.23.255510
1340.167.24.0/2340.167.24.1 to 40.167.25.25440.167.25.255510
1440.167.26.0/2340.167.26.1 to 40.167.27.25440.167.27.255510
1540.167.28.0/2340.167.28.1 to 40.167.29.25440.167.29.255510
1640.167.30.0/2340.167.30.1 to 40.167.31.25440.167.31.255510
1740.167.32.0/2340.167.32.1 to 40.167.33.25440.167.33.255510
1840.167.34.0/2340.167.34.1 to 40.167.35.25440.167.35.255510
1940.167.36.0/2340.167.36.1 to 40.167.37.25440.167.37.255510
2040.167.38.0/2340.167.38.1 to 40.167.39.25440.167.39.255510
2140.167.40.0/2340.167.40.1 to 40.167.41.25440.167.41.255510
2240.167.42.0/2340.167.42.1 to 40.167.43.25440.167.43.255510
2340.167.44.0/2340.167.44.1 to 40.167.45.25440.167.45.255510
2440.167.46.0/2340.167.46.1 to 40.167.47.25440.167.47.255510
2540.167.48.0/2340.167.48.1 to 40.167.49.25440.167.49.255510
2640.167.50.0/2340.167.50.1 to 40.167.51.25440.167.51.255510
2740.167.52.0/2340.167.52.1 to 40.167.53.25440.167.53.255510
2840.167.54.0/2340.167.54.1 to 40.167.55.25440.167.55.255510
2940.167.56.0/2340.167.56.1 to 40.167.57.25440.167.57.255510
3040.167.58.0/2340.167.58.1 to 40.167.59.25440.167.59.255510
3140.167.60.0/2340.167.60.1 to 40.167.61.25440.167.61.255510
3240.167.62.0/2340.167.62.1 to 40.167.63.25440.167.63.255510
3340.167.64.0/2340.167.64.1 to 40.167.65.25440.167.65.255510
3440.167.66.0/2340.167.66.1 to 40.167.67.25440.167.67.255510
3540.167.68.0/2340.167.68.1 to 40.167.69.25440.167.69.255510
3640.167.70.0/2340.167.70.1 to 40.167.71.25440.167.71.255510
3740.167.72.0/2340.167.72.1 to 40.167.73.25440.167.73.255510
3840.167.74.0/2340.167.74.1 to 40.167.75.25440.167.75.255510
3940.167.76.0/2340.167.76.1 to 40.167.77.25440.167.77.255510
4040.167.78.0/2340.167.78.1 to 40.167.79.25440.167.79.255510
4140.167.80.0/2340.167.80.1 to 40.167.81.25440.167.81.255510
4240.167.82.0/2340.167.82.1 to 40.167.83.25440.167.83.255510
4340.167.84.0/2340.167.84.1 to 40.167.85.25440.167.85.255510
4440.167.86.0/2340.167.86.1 to 40.167.87.25440.167.87.255510
4540.167.88.0/2340.167.88.1 to 40.167.89.25440.167.89.255510
4640.167.90.0/2340.167.90.1 to 40.167.91.25440.167.91.255510
4740.167.92.0/2340.167.92.1 to 40.167.93.25440.167.93.255510
4840.167.94.0/2340.167.94.1 to 40.167.95.25440.167.95.255510
4940.167.96.0/2340.167.96.1 to 40.167.97.25440.167.97.255510
5040.167.98.0/2340.167.98.1 to 40.167.99.25440.167.99.255510
5140.167.100.0/2340.167.100.1 to 40.167.101.25440.167.101.255510
5240.167.102.0/2340.167.102.1 to 40.167.103.25440.167.103.255510
5340.167.104.0/2340.167.104.1 to 40.167.105.25440.167.105.255510
5440.167.106.0/2340.167.106.1 to 40.167.107.25440.167.107.255510
5540.167.108.0/2340.167.108.1 to 40.167.109.25440.167.109.255510
5640.167.110.0/2340.167.110.1 to 40.167.111.25440.167.111.255510
5740.167.112.0/2340.167.112.1 to 40.167.113.25440.167.113.255510
5840.167.114.0/2340.167.114.1 to 40.167.115.25440.167.115.255510
5940.167.116.0/2340.167.116.1 to 40.167.117.25440.167.117.255510
6040.167.118.0/2340.167.118.1 to 40.167.119.25440.167.119.255510
6140.167.120.0/2340.167.120.1 to 40.167.121.25440.167.121.255510
6240.167.122.0/2340.167.122.1 to 40.167.123.25440.167.123.255510
6340.167.124.0/2340.167.124.1 to 40.167.125.25440.167.125.255510
6440.167.126.0/2340.167.126.1 to 40.167.127.25440.167.127.255510
6540.167.128.0/2340.167.128.1 to 40.167.129.25440.167.129.255510
6640.167.130.0/2340.167.130.1 to 40.167.131.25440.167.131.255510
6740.167.132.0/2340.167.132.1 to 40.167.133.25440.167.133.255510
6840.167.134.0/2340.167.134.1 to 40.167.135.25440.167.135.255510
6940.167.136.0/2340.167.136.1 to 40.167.137.25440.167.137.255510
7040.167.138.0/2340.167.138.1 to 40.167.139.25440.167.139.255510
7140.167.140.0/2340.167.140.1 to 40.167.141.25440.167.141.255510
7240.167.142.0/2340.167.142.1 to 40.167.143.25440.167.143.255510
7340.167.144.0/2340.167.144.1 to 40.167.145.25440.167.145.255510
7440.167.146.0/2340.167.146.1 to 40.167.147.25440.167.147.255510
7540.167.148.0/2340.167.148.1 to 40.167.149.25440.167.149.255510
7640.167.150.0/2340.167.150.1 to 40.167.151.25440.167.151.255510
7740.167.152.0/2340.167.152.1 to 40.167.153.25440.167.153.255510
7840.167.154.0/2340.167.154.1 to 40.167.155.25440.167.155.255510
7940.167.156.0/2340.167.156.1 to 40.167.157.25440.167.157.255510
8040.167.158.0/2340.167.158.1 to 40.167.159.25440.167.159.255510
8140.167.160.0/2340.167.160.1 to 40.167.161.25440.167.161.255510
8240.167.162.0/2340.167.162.1 to 40.167.163.25440.167.163.255510
8340.167.164.0/2340.167.164.1 to 40.167.165.25440.167.165.255510
8440.167.166.0/2340.167.166.1 to 40.167.167.25440.167.167.255510
8540.167.168.0/2340.167.168.1 to 40.167.169.25440.167.169.255510
8640.167.170.0/2340.167.170.1 to 40.167.171.25440.167.171.255510
8740.167.172.0/2340.167.172.1 to 40.167.173.25440.167.173.255510
8840.167.174.0/2340.167.174.1 to 40.167.175.25440.167.175.255510
8940.167.176.0/2340.167.176.1 to 40.167.177.25440.167.177.255510
9040.167.178.0/2340.167.178.1 to 40.167.179.25440.167.179.255510
9140.167.180.0/2340.167.180.1 to 40.167.181.25440.167.181.255510
9240.167.182.0/2340.167.182.1 to 40.167.183.25440.167.183.255510
9340.167.184.0/2340.167.184.1 to 40.167.185.25440.167.185.255510
9440.167.186.0/2340.167.186.1 to 40.167.187.25440.167.187.255510
9540.167.188.0/2340.167.188.1 to 40.167.189.25440.167.189.255510
9640.167.190.0/2340.167.190.1 to 40.167.191.25440.167.191.255510
9740.167.192.0/2340.167.192.1 to 40.167.193.25440.167.193.255510
9840.167.194.0/2340.167.194.1 to 40.167.195.25440.167.195.255510
9940.167.196.0/2340.167.196.1 to 40.167.197.25440.167.197.255510
10040.167.198.0/2340.167.198.1 to 40.167.199.25440.167.199.255510
10140.167.200.0/2340.167.200.1 to 40.167.201.25440.167.201.255510
10240.167.202.0/2340.167.202.1 to 40.167.203.25440.167.203.255510
10340.167.204.0/2340.167.204.1 to 40.167.205.25440.167.205.255510
10440.167.206.0/2340.167.206.1 to 40.167.207.25440.167.207.255510
10540.167.208.0/2340.167.208.1 to 40.167.209.25440.167.209.255510
10640.167.210.0/2340.167.210.1 to 40.167.211.25440.167.211.255510
10740.167.212.0/2340.167.212.1 to 40.167.213.25440.167.213.255510
10840.167.214.0/2340.167.214.1 to 40.167.215.25440.167.215.255510
10940.167.216.0/2340.167.216.1 to 40.167.217.25440.167.217.255510
11040.167.218.0/2340.167.218.1 to 40.167.219.25440.167.219.255510
11140.167.220.0/2340.167.220.1 to 40.167.221.25440.167.221.255510
11240.167.222.0/2340.167.222.1 to 40.167.223.25440.167.223.255510
11340.167.224.0/2340.167.224.1 to 40.167.225.25440.167.225.255510
11440.167.226.0/2340.167.226.1 to 40.167.227.25440.167.227.255510
11540.167.228.0/2340.167.228.1 to 40.167.229.25440.167.229.255510
11640.167.230.0/2340.167.230.1 to 40.167.231.25440.167.231.255510
11740.167.232.0/2340.167.232.1 to 40.167.233.25440.167.233.255510
11840.167.234.0/2340.167.234.1 to 40.167.235.25440.167.235.255510
11940.167.236.0/2340.167.236.1 to 40.167.237.25440.167.237.255510
12040.167.238.0/2340.167.238.1 to 40.167.239.25440.167.239.255510
12140.167.240.0/2340.167.240.1 to 40.167.241.25440.167.241.255510
12240.167.242.0/2340.167.242.1 to 40.167.243.25440.167.243.255510
12340.167.244.0/2340.167.244.1 to 40.167.245.25440.167.245.255510
12440.167.246.0/2340.167.246.1 to 40.167.247.25440.167.247.255510
12540.167.248.0/2340.167.248.1 to 40.167.249.25440.167.249.255510
12640.167.250.0/2340.167.250.1 to 40.167.251.25440.167.251.255510
12740.167.252.0/2340.167.252.1 to 40.167.253.25440.167.253.255510
12840.167.254.0/2340.167.254.1 to 40.167.255.25440.167.255.255510

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses